Vereth the Cunning on the Rise of Suffering wants you to kill Baelok, the Rider of Blood.
Baelok is one of the few vrykul that I've ever seen rise through the ranks, and that was mostly accomplished through shear brutality. If your competition ends up dead, there's far less to compete against.
When you join battle with him, spread out from your companions and keep your distance as much as you reasonably can. He will not hesitate to steal your life force for himself, so you will need to hinder his ability to do so as much as possible.
You have my confidence. See to it that he dies.